Improving Quality of Carotid Interventions: Identifying Hospital-Level Structural Factors that can Improve Outcomes

BACKGROUND: “Structural factors” relating to organization of hospitals may affect procedural outcomes. This study's aim was to clarify associations between structural factors and outcomes after carotid endarterectomy (CEA) and carotid endarterectomy stenting (CAS). METHODS: A systematic review of studies published in English since 2005 was conducted. Structural factors assessed were as follows: population size served by the vascular department; number of hospital beds; availability of dedicated vascular beds; established clinical pathways; surgical intensive care unit (SICU) size; and specialty of surgeon/interventionalist. Primary outcomes were as follows: mortality; stroke; cardiac complications; length of hospital stay (LOS); and cost. RESULTS: There were 11 studies (n = 95,100 patients) included in this systematic review. For CEA, reduced mortality (P < 0.0001) and stroke rates (P = 0.001) were associated with vascular departments serving >75,000 people. Larger hospitals were associated with lower mortality, stroke rate, and cardiac events, compared with smaller hospitals (less than 130 beds). Provision of vascular beds after CEA was associated with lower mortality (P = 0.0008) and fewer cardiac events (P = 0.03). Adherence to established clinical pathways was associated with reduced stroke and cardiac event rates while reducing CEA costs. Large SICUs (≥7 beds) and dedicated intensivists were associated with decreased mortality after CEA while a large SICU was associated with reduced stroke rate (P = 0.001). Vascular surgeons performing CEA were associated with lower stroke rates and shorter LOS (P = 0.0001) than other specialists. CAS outcomes were not influenced by specialty but costless when performed by vascular surgeons (P < 0.0001). CONCLUSIONS: Structural factors affect CEA outcomes, but data on CAS were limited. These findings may inform reconfiguration of vascular services, reducing risks and costs associated with carotid interventions.